Import export cost optimization

List of the contents of this article:

• 1, Generally optimize the linux kernel, what parameters need to be optimized
• 2, Linux service startup optimization
• 3, Linux memory optimization linux memory optimization
• 4, If you are given a service, what optimization do you need to do in the Linux system?
• 5
  、 What are the methods of Linux performance tuning?

Generally optimize the kernel of linux, needWhat parameters are optimized

The kernel performance of the Linux system can be improved in many ways. Here are some common methods: Adjust TCP/IP parameters: TCP/IP network performance can be optimized by modifying kernel parameters. For example, you can control the retention time of TCP connection by modifying the tcp_keepalive_time parameter.

In fact, the most direct optimization of Linux for personal use is to upgrade the kernel. The kernel compiled by yourself is compiled according to your own system, which will get the maximum performance and the smallest kernel. However, the server is different. Of course, we also hope that each server is a manually compiled kernel, which is efficient and exquisite.

A complete Linux kernel generally consists of 5 parts, which are memory management, process management, inter-process communication, virtual file system and network interface. Memory management Memory management mainly accomplishes how to manage the physical memory of the whole system reasonably and effectively, while quickly responding to requests for memory allocation from various subsystems of the kernel.

Generally speaking, Linux servers do not need GUI, so management tasks can be completed under the command line, so it is better to turn off GUI.

MySQL on Linux optimizes and improves performance, which can optimize and close NUMA features as follows: These actually come from the latest technology of CPU: energy-saving mode. The operating system cooperates with the CPU hardware. When the system is not busy, it will reduce the frequency of the CPU in order to save electricity and reduce the temperature.

How to optimize the performance of the Linux system Premise We can make a list at the beginning of the article, listing some tuning parameters that may affect the performance of the Linux operating system, but it is actually of no value. Because performance tuning is a very difficult task, it requires a fairly in-depth understanding of hardware, operating systems, and applications.

Linux service startup optimization

Most Linux systems will start sshd (security Shell service), syslog (system log tool) and lpd (printing service) Service), but there will be more services to be launched. Too many services will increase the startup time, and optimizing and closing unnecessary services will improve the startup time.

In fact, the most direct optimization of Linux for personal use is to upgrade the kernel. The kernel compiled by yourself is compiled according to your own system, which will get the maximum performance and the smallest kernel. However, the server is different. Of course, we also hope that each server is a manually compiled kernel, which is efficient and exquisite.

System upgrade: You can consider upgrading the system kernel, software packages and applications to improve system performance. Service optimization: You can consider optimizing the services running in the system, such as database servers or web servers, to improve performance.

Linux memory optimization linux memory optimization

1. Unless it is set to --interleave=nodes poll allocation, that is, memory can be allocated in this way on any NUMA node. In other ways, even if there is extra memory on other NUMA nodes, Linux will not allocate the remaining memory to this process, but uses SWAP to obtain memory.

2. Virtual memory optimization First, check the usage of virtual memory, and use the command free to check the memory usage of the current system. Generally speaking, the physical memory of Linux is almost completely used.

3. Clean up the thumbnail cache. For most systems with Linux as the kernel (including Android), there will be thumbnai.L, which can be literally translated as "thylnail", that is to say, Ubuntu will automatically create a thumbnail version and store it in the file manager.

4. 6GB of memory marked as active page memory should not be exchanged, because the memory page often needs to move between RAM and disk, which will reduce performance. If the amount of swap is greater than inactive (anonymous) memory, you should add more RAM to optimize Linux memory pages.

5. The following are some specific measures to optimize the performance of Linux system hard disk. Clean up the disk. This method seems very simple: clean up the disk drive, delete unnecessary files, and clear all files that need to be saved but will not be used. If possible, clear the redundant directories and reduce the number of subdirectories.

If you are given a service, what optimization do you need to do in the Linux system?

1. In fact, the most direct optimization of Linux used by individuals is to upgrade the kernel. The kernel compiled by yourself is compiled according to your own system, which will get the maximum performance and the smallest kernel. However, the server is different. Of course, we also hope that each server is a manually compiled kernel, which is efficient and exquisite.

2. Let's mainly look at the stage after the kernel is loaded. You can run the runlevel command to determine the current running level of your system. When the kernel is loaded and starts to run, it will be adjusted.Use the /sbin/init program, which runs as root and is set to "run level" as required when booting starts.

3. 12 steps for Linux system optimization: log in to the system. SSH remote control is prohibited. Time synchronization. Configure the yum update source. Turn off selinux and iptables. Adjust the number of file descriptors. Regularly and automatically clean up /var/spool/clientmquene/directory junk files. Simplise the boot service.

4. It's also very good to use. Top ten best systems in Linux? Ubuntu. Ubuntu is an open source Linux operating system based on Debian. Ubuntu is very popular, and many other distributions are derived from it.Ubuntu server is very effective in building high-performance, highly scalable, flexible and secure enterprise data centers.

5. However, in busy servers, over time, file fragmentation will reduce the performance of the hard disk, and the performance of the hard disk can only be noticed when reading or writing data from the hard disk. The following are some specific measures to optimize the performance of the hard disk of the Linux system.

What are the methods of Linux performance tuning?

Of course, the best way is to close it in the BIOS. Ii) Let's take a look at vm.swappiness again. Vm.swappiness is a strategy for the operating system to control the exchange of physical memory. The value it allows is a percentage value, the minimum is 0, the maximum is 100, and the default value is 60.

Service optimization: You can consider optimizing the services running in the system, such as database servers or web servers, to improve performance. Hardware optimization: You can consider upgrading hardware, such as memory, CPU, disk, etc., to improve performance.These are common ways to optimize Linux systems.

Log in to the system. SSH remote control is prohibited. Time synchronization. Configure the yum update source. Turn off selinux and iptables. Adjust the number of file descriptors. Regularly and automatically clean up /var/spool/clientmquene/directory junk files. Simplise the boot service.

Event-based sampling is that OProfile only records the number of occurrences of specific events (such as L2 cache failure). When the fixed value set by the user is reached, Oprofile records it (ta sample). This method requires a Performance Counter inside the CPU.